Bill Bridgeman was a pioneering test pilot, once known as the fastest man alive. He told his story in a best-selling book called "The Lonely Sky," in 1955. The book has been reissued, and recalls a time when flight records were broken almost monthly, a time famously chronicled in Tom Wolfe's 1979 book "The Right Stuff." "The Lonely Sky" was a best-seller two decades before that, and remains a classic for aviation fans.

Bridgeman tested experimental airplanes for the Douglas Aircraft Company. Flying an advanced craft called the Skyrocket in August 1951, he reached Mach 1.88 - nearly twice the speed of sound - and claimed the world speed record and unofficial altitude record. Bridgeman appeared on the cover of "Time" magazine, hailed as the "Fastest Man Alive."

His achievement surpassed a flight four years earlier by famed test pilot Chuck Yeager, who was the first aviator to break the sound barrier in the X-1 experimental aircraft. Yeager went on to claim other records, however, and his fame kept growing.

Bridgeman's wife and coauthor, Jackie Hazard, was a former reporter, and says she and her husband met when a newspaper sent her to interview him.

Hazard says Yeager and Bridgeman were colleagues and rivals, and Yeager at times flew the "chase plane," watching tests of the experimental aircraft. During one such test flight, she says, Bridgeman's plane went into a spin, something the engineers had warned against.

"Now, down below on the ground, all these engineers are listening," says Hazard. "So he didn't obviously say anything and Chuck doesn't say anything, and Bill goes into a spin. And Chuck just follows him down and he gets to the end of the spin, pulls out, and Chuck looks over and says, 'Oops.'"

She says test pilots protected each other, and Yeager was covering for his friend, even though engineers learned what happened by examining data from the test flight. They had been tipped off by Yeager's humorous exclamation.

By late 1953, other pilots, including Scott Crossfield, would go on to break speed records, approaching and passing Mach 2. And Chuck Yeager would go on to claim more speed and altitude records.

Hazard remembers her late husband as a quiet but confident man, a trait he shared with his fellow test pilots.

"I think most of the test pilots are extremely confident. And they're not much for small talk. Bill never was, but he had a great sense of humor... He didn't like the publicity he got at all, but he put up with it" says Hazard.

Bridgeman tried to join the corps of U.S. astronauts through the Air Force, but was not chosen for the program after the National Aeronautics and Space Administration was formed in 1958. The new space agency, known as NASA, favored fliers who were engineers, and many veteran test pilots like Yeager and Bridgeman found themselves left out of the program.

Hazard says these men had a pioneering spirit.

"I don't think you can say the same thing about astronauts, because that's engineering and it's mechanical and it's technical," says Hazard. "They've got courage. I'm not saying they don't have courage. You've got to have courage to get in one of those things. But it's not the same as the test pilot. They're a different breed entirely."

She says the early pilots who pierced the upper reaches of the atmosphere had a spirit of independence. Most were veteran fliers from World War II, but she says test flights were different, because Bridgeman and the other pilots on those experimental missions had only their flying skills to rely on in case of trouble.

"When he was out in the Pacific flying, he wasn't alone. He had all of his buddies [in the sky near him] and they were all going out to bomb the Japanese islands or something. But when you're waiting for this flight in the Skyrocket, you're alone," says Hazard.

After many dangerous flights in experimental aircraft, Bridgeman retired and began flying routine commercial flights from Long Beach to Catalina Island, off the coast of California. One calm day in 1968, his airplane plummeted into the ocean and he was killed instantly at the age of 53. No one ever learned the reason for the crash; there was speculation that he had suffered a heart attack or that mechanical failure brought down the airplane.

Hazard says her husband's legacy can still inspire future pioneers who are willing to push the limits.